Cutting tool



138020, l949 E. G. sTURGEoN ET A1. 2,491,525

CUTTING TOOL Filed Feb. 5, 194B Patented Dec. 20, 1949 STAT-Es foFFilzcECUTTING TOOL corporation of `Michigan fApplicatioriFebruary 5, 1948,lSerial"No.`6;438

n6 Claims.

`l 1' This invention relates-broadlyV to new: and useful improvements incouplings .and more particularly to =a device of this character'whichisprimarny adapted though noi-l limited Vforuse'in cutting tools.

A typical use for the couplingtis-toifastenfa cutteriinra holder; and,4when used in .this capacity, the coupling` establishes apositive-nonchatteringfdrive between the parts. Since J'the coupling isprimarily intended for this purposeiit isfsorshownand described byway ofillustration in thisvapplication. vBut it isato be understoodthatinitsifbroader aspectsthe coupling can be `applied to any revolving`driving mechanism such'as line shafting 'or` arbors inmilling machines.

' important object ofthe invention iis "to provide a coupling whichnermitsza driven `:elementtoiz-be easily and` quickly fastened vto .or`disengaged" from the driving. member.

.iStillfanother object ofthe `rnesent invention isto'provide as couplingof the aboveementioned character wherein; the drivenfelernent: has ataperedcshankrwhich iitsin a correspondinglvrtaperedfsocket in thedriving member Land; includes novel means f for maintaining the shank`pressed soldlyagainstthe wall of the sofketlatalltimes.

Still another Aobject `oi the invention: is to' provideacoupling of theabove-mentioned character which is uniquely constructed sothat' itwillnot be released inadvertently inoperation.

Yet another obiect of the invention `is to vprovidea `coupling of theabove-mentioned character whereinthe drivingr member interengages withthe driven element `to provide a"positive"rotary 1.;

drive therebetween.

*Other objects vadvantages of the invention willbe-apparent during thecourseoi the following description.

In `the drawing forming apart of'this specifica.. tion and wherein likenumerals are employedto designate like parts throughout the saine,

' Figure 1 isa side elevational View of a cutting toolrin which theholder and cutter are detach` ably fastened together by a couplingembodying theV invention;

""Fg'. V2 is a View partly in section and partly in elevation'takengenerallyeon the line `22 of Figurell;

1ig.`3 is-a transverse sectional viewtakenon the line`3-3 of Fig. 2;

, Fig. `iis a transverse sectional viewtaken on the line 4--4 of Fig. 2;

' "Fig-*5 'isa transverse sectional view taken on ..Fig..6: is `a,-`perspective* view *of' a clamping elementembodying azpartof theinvention.

:Broadly the `cutting tool here lshown comprises acutter Iliand aholderI2 for the. cutter. `The cutter Ill` is ydisposedebelow `and infcoaxialrelation with-.theholderi I2. 'Usually both the cutter IB andtheholderflft` will be generally cylindrical in: shape` as shown in the.drawing. "At its upper end the holder I2V is provided Witha' taperedshank i4-which terminates inthe'` usual tang I6. :Both the shankVlid-and the-tangfl areconventionalin devices of this lcharacter andtheir purpcse'is tot in-:andfconnect the holder tozthe drivingspindlevof a boringgmachineor'drll press '(not shown). :The cutter AIilhere shown :by Away of illustrationis racounterbore, but it will bereadily appreciated that the presentinvention can be adapted to anytype'of cutting tool. This invention is concerned primarilywlthmeans:forfastening `theputterIil tothe 'holder I2.

`-To this end, thefcutter lil is" provided atthe upper end: thereof witha` longitudinally tapered shank 4t8 which extendsinto and snugly iiits acorrespondingly tapered sccketzk'l in the lower endl of holder I2. vrAnysuitable taper-may be providedkforvthe shank I3, but the taper anglewall of:socl-zei',.2ll,-and` the shank sustains the full ai i) thrustimposed on the cutter. However, inorder to transmitrotarydrive ortorquefrom the holder to the cutter, the shoulder 22 isfashionedto provide oneor more upwardly extending lugs 24 and the lower end of the holder I2 isformed with a corresponding number i of downwardly projecting lugs 26.Inthe form ofthe invention hereshown by way of illustration, the cutterI El is `formed I" with two lugs `24 asdiametrcally opposedsides thereofand the holder I2 .is formed `wthitwo correspondinglylocated lugs 26.When the cutter I0 isinterengaged with the holder I2, thelugs 26 abutagainst the lugs '24 to establish apositive rotary drive therebetween.Thus, the lugs 26 push against the lugs 2!! to transmit driving torquefrom the `holder to the cutter.

j` In cutting tools ,of this type, there isa tendency foi-"the cutterdtto chatterinthefhlder 112 when` the device is,` in use even'thoughipressure ,tisim-j( posed continuously axially thereagainst.Also, there is a tendency for the cutter to pull out of the holderinadvertently on occasion, as when the tool is withdrawn from the Work.The problem is to provide a connection between the cutter I and theholder I2 which will be readily releasable and at the same time willhold the cutter in such manner as to prevent chattering or inadvertentdisengagement.

VThe connection here shown achieves all of the results set forth aboveand comprises a clamping member 28 mounted for longitudinal slidingmovement in an axial groove or guideway 30 in the holder I2. Theguideway 30 opens into and extends radially outwardly from the socket 20to position the clamping member 28 laterally of the shank I8. Clampingmember 28 is generally in the form of an elongated bar, as shown in Fig.6, and the lower end thereof is formed with an inturned extension or lug32 which projects into an annular groove 34 in shank I8. An axial slot36 in th'e portion of shank I8 above annular groove 34 accommodates thelug 32 when the shank is inserted into the socket. According to thepresent invention, the tapered socket 20 terminates in an axial bore 38and the guideway 30 extends the full length of the combined socket andbore. A spring retainer 40 is mounted in the bore 38 behind shank I8,and a spring 42 is supported in the bore by the retainer. In thisconnection, it will be observed that the clamping member 28 extends intothe bore 33 beside retainer 4I) and spring 42 and that it is formed witha shoulder 44 which seats downwardly against the upper end of spring 42.Thus, the spring 42 limits outward axial movement of the locking member28; and, when compressed, it will urge the locking member axially intothe holder I2.

According to the present invention, the lug 32 is formed with aninclined or beveled top surface 46 which is located so that the loweredge thereof just clears the'upper radial wall of groove 34 when theshank I8 has been fully inserted in the socket 20. If the cutter I0 isthen rotated in a clockwise direction, as shown by the arrow in Fig. 2,the upper radial edge of the groove 34 rides along the surface 46 andcams the clamping member 28 downwardly against the action of spring 42.The cutter I8 can be rotated in this manner until lugs 24 and 26interengage as shown in Fig. 1 to prevent further rotation. Thereafter,the compressed spring 42 reacts through the clamping member 28 tomaintain the shank I8 pressed solidly against the wall of socket 20.

From the foregoing, it will be readily apparent that the clamping member28 and groove 34 collectively constitute a cam means which becomesoperative upon rotation of shank I8 to compress the spring 42. As longas the spring 42 is under compression, there is a constant force holdingthe shank I8 against the wall of socket 28; and, in practice, this forceis suicient to prevent chattering of the cutter I0 during operation ofthe tool. Further, when the cutter II) is rotated to compress spring 42,the lug 32 moves out of alignment with the axial groove 36 so that thelug is axially interlocked with the groove 34 to prevent the cutter frominadvertently disengaging the holder I2.

In this connection, it will be apparent that the cutter Ill can bedisengaged from the holder I2 only by rotating the cutter in acounterclockwise direction until the axial groove 35 again moves intoregister with the lug 32. Manifestly, yas the cutter is rotated in theabove manner, spring 42 is progressively released; and, by the time thegroove 36 moves into register with clamping member 28, the spring is nolonger under compression. Cutter I0 can then -be easily withdrawn fromthe holder I2.

While any type of conventional retainer may be used for spring 42, welprefer to employ a snap ring of the type shown in Fig. 3. This ring tssnugly in an annular groove 48 in the wall of bore 38 behind shank I8.The ends of the snap ring 40 are spacedas shown in Fig. 3, and the ringis compressed for assembly or disassembly by inserting the jaws of aconventional sharp-nosed pliers in holes 50 and 52 provided in theterminal portions of the ring. This arrangement permits the parts to beassembled or disassembled easily and quickly and at the same time holdsthe parts properly assembled in the holder.

Only one clamping member 28 is here shown but it will be readilyapparent that two or more clamping members may be employed if necessaryor desirable. clamping member is suflicient for usual types and sizes ofcutting tools; but any desired number may be used depending on theexigencies of the particular situation.

The cutter ID here shown has the usual pilot pin 54 which extendsaxially therethrough and is secured by a nut 58 in the conventionalmanner.

It is to be understood that the form of the invention herewith shown anddescribedis to be taken as a preferred example of the same and thatvarious changes in the size, shape, and arrangement of parts may beresorted to without departing from the spirit of the invention 'or thescope of the appended claims.

Having thus described the invention, we claim:

1. A coupling comprising a driving member having an inwardly taperedsocket; a driven element having a correspondingly tapered shank disposedin the socket, said shank provided with a radial shoulder; a slidableclamping member beside said shank, said clamping member having a radialprojection engaging under said shoulder;"

and resilient means behind said shank coactive with said clamping memberto urge said radial extension against said shoulder and to force saidshank solidly against the wall of the socket.

2. A coupling comprising a driving member having an inwardly taperedsocket; a driven member having a correspondingly tapered shank disposedin the socket, said shank provided with a radial shoulder; a slidableclamping member in the socket beside said shank, said clamping memberhaving a radial projection engaging under said shoulder and a radialseat behind said shank; and resilient means in the socket behind theshank acting against said radial seat to urge the clamping memberaxially into the socket and to force said radial extension against saidshoulder whereby to maintain Y said shank pressed solidly against thewall of the socket. Y

3. A coupling comprising a driving member having an inwardly taperedsocket provided with a longitudinal guideway; a driven element having acorrespondingly tapered shank disposed in said socket, said shankprovided with a radial. shoulder; a clamping member longitudinallyslidable in the guideway, said clamping member having a radialprojection engaging under said shoulder and a spring seat behind saidshank; and spring means in the socket behind the shank acting againstsaid seat to urge the clamping member into the socket and to force saidradial extension In practice, we have found that one' 5 against saidshoulder to maintain said shank pressed solidly against the wall of saidsocket.

4. The combination as set forth in claim 3 wherein said shank is formedwith a longitudinal guideway which accommodates the radial projection onthe clamping member when the shank is inserted into the socket, andwherein said radial projection comprises a cam element which coacts withsaid shoulder to move the clamping member axially against said springmeans when the shank is rotated in the socket.

5. A coupling comprising a driving member having an inwardly taperedsocket; a driven element having a correspondingly tapered shank disposedin said socket; spring means in the socket behind said shank; andretaining means having portions providing seats for said spring meansand including cam means operable by rotation of the shank in said socketto compress said spring means, said spring means acting against saidseats and through said cam means to maintain said shank pressed solidlyagainst the wall of said socket.

6. A coupling comprising a driving member having an inwardly taperedsocket; a driven f.

element having a correspondingly tapered shank disposed in said socket;a removable spring retainer in the socket behind said shank; springmeans in the socket behind said spring retainer; and cam means operableby rotation of the shank in the socket to compress said spring meansagainst said retainer, and said spring means being reactive through saidcam means to maintain the shank pressed solidly against the Wall of thesocket.

EDWARD G. STURGEON.

FRANZ VON VALTIER.

LEE WIEDENBECK.

LEON N. BUTLER.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,766,136 Markstrum June 24, 19301,824,509 Snader Sept. 22, 1931 1,837,639 Wickersham Dec. 22, 19312,057,143 Gairing Oct. 13, 1936 2,059,496 Smith Nov. 3, 1936 2,118,485Brown May 24, 1938

